Doctor support



April 16, 1968 w. P. DAPSES 3,377,645

DOCTOR SUPPORT Filed Aug. 4, 1965 INVENTOR WILLIAM R DAPSES ATTORNEY United States Patent 3,377,645 DOCTOR SUPPORT William P. Dapses, Salem, Greg, assigner to Lodding Engineering Corporation, Auburn, Mass., a corporation of Massachusetts Filed Aug. 4, 1965, Ser. No. 477,200 2. Claims. (Ql. 15-45651) ABSTRACT OF THE DISCLOSURE A doctor supporting means for a doctor blade wherein the doctor blade support is journaled on bearings at the ends thereof but the effective supports are inwardly of the ends, i.e., intermediate the ends of the support, to prevent deflection of the support and the doctor blade itself when it is applied with pressure against the roll to be doctored.

It is well known that any continuously loaded member such as a doctor blade bearing against a roll being doctored results in a falling dimension of pressure as the center line of the member is approached. Since the doctor is supported at its ends, at the sides of the machine to which it is applied, this effect is made worse by torsional loading at the ends for maintaining or attempting to maintain the doctor blade in close contact with the doctor at all points.

This results in a deflection of the blade and the supporting doctor at the center of the machine, and it is the general purpose of the present invention to reduce or eliminate this flexure.

This is accomplished by providing in general for supports, not at the ends of the doctor, but inwardly thereof in positions which may be determined or adjusted, and this is done by providing loading anchors on the doctor intermediate the ends thereof to which anchors are secured in bearings on the doctor so that they are free to rotate relative thereto but have a supporting action. Pneumatic loading arms being secured to these journals, the doctor and its blade is loaded in order to hold the blade to the roll in the desired manner, but the point of the supports for the doctor are intermediate the ends thereof and not at the ends, and therefore the resistance to the deflection toward the center of the device is eliminated or substantially so. Torsion is applied to the journals rather than to the ends of the doctor, and the journals are connected in fixed relationship with respect to the doctor only intermediate the ends thereof.

Other objects and advantages of the invention will appear hereinafter.

Reference is to be had to the accompanying drawings in which:

FIG. 1 is a perspective view illustrating the invention, and

FIG. 2 is a View in elevation illustrating the same.

In the drawing, indicates the roll which is to be doctored by means of the blade 12 held in the doctor or doctor back 14. As usual there is provided a pneumatic loading arm at each end as at 16 operated by a cylinder 18 for providing a torsional force to the doctor so as to maintain the blade pressed against the roll. In the usual case however the journals 20 to which the arms 16 are secured are merely bolted to the ends of the doctor 14 whereas in the present case they are journaled in close fitting sleev type bearings 22, 22, there being as shown in FIG. journals 2% at each end of the machine.

These journals 20 are rotatable and slidable in the bea ings 22 and each is provided with a head or the like 24 which is bolted in a fixed relationship with respect 1 the loading anchors 26 which are secured directly acro the angle of the doctor back.

The position of the anchors 26 may vary according 1 the installation or to the length of the doctor back an at least theoretically can be located just about centrall i.e., halfway between the ends of the doctor down to location about one-quarter of the way inwardly from t]: respective end of the doctor.

It will therefore be seen that the pneumatic loading directed to the journals which are able to rotate slight] in the bearings at 22 under influence of the torsion: forces involved, and turning screws and shims are then fore completely done away with. The journals can t supported in the usual brackets 28.

This construction results in a more even distributio of the blade pressure against the roll face but it is tru that the relatively long journals will twist somewhat mor than the conventional short journals for any given torqu loading. On the other hand it has been found that thi torsion under uniform blade pressure of ten pounds pe inch in a doctor 240" long amounts only to 0.8 of a dc gree which is neglible.

Having thus described my invention and the advar tages thereof, I do not wish to be limited to the detail herein disclosed, otherwise than as set forth in the claim: but what I claim is:

1. The combination of a roll having a surface to b doctored and an elongated doctor, said doctor includin means for holding a doctor blade to the roll surface, an. means supporting the doctor,

said doctor supporting means comprising a pair of elon gated elements extending longitudinally of the doc tor, said elements extending inwardly from the end of the doctor and terminating at points intermediatl the center of the doctor and the ends of the doctor said means also extending outwardly of the ends 0 the doctor providing for inner ends and outer end with respect to the doctor,

the inner ends of said elements being secured directl to the doctor in fixed relation with respect thereto a points intermediate the center of the doctor and tln ends thereof, means applying torsion to said element: to tend to turn said doctor in a direction so that tht blade enters into doctoring relationship with respec to said roll surface, and sleeve-like bearings in fixer relation on the doctor, one at each end thereof, tht elongated elements extending through said bearing: and being rotatable and slidable in said bearings.

2. The combination of claim 1 wherein the element: are substantially free of the doctor except at their innei ends.

References Cited UNITED STATES PATENTS 1,566,358 12/1925 White 15-2565] 3,087,185 4/1963 Washburn 15--256.51 CHARLES A. WILLMUTH, Primary Examiner. L. MACHLIN, Assistant Examiner. 

